bobkrech
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You might find this download useful. https://www.scribd.com/doc/17390328/Introduction-to-Lathe-OperationsGraphite is messy. I lay craft paper down to catch most of it, and use a piece to shield the spray of powder and direct it down into the catch below. Get 95% of it without a vacuum. Going slower helps too.
The bit does seem to gring more than cut, but it still works. That is why they do not need to me sharp. My tools for entrance and exit cones are wood spade bits ground to the proper angles. Don't need to be sharp, but you must grind the edge to 45 degrees to reduce friction.
Machining is all abour speeds, feeds, angles and fixturing. You need to learn how each tool removes material and set it up properly.
Tools have to be sharp or they will heat up the work piece, but they are not sharpened like a knife. A good lathe tool is kept sharp with a diamond sharpening stone. They work on HHS or carbide equally well.
If you run the lathe at too high a speed, or try to cut with a dull tool, both the tool and the workpiece will get hot. The workpiece will expand with the heat, and will be too small after it cools. The tool will get dull and possibly break, or break the workpiece. A lubricant, which can be any oil in a pinch will keep the tool sharp and cool and produce a smoother surface.
You can machine SS with HHS or carbide equally well, but you can run the lathe faster with carbide. I actually get a better finish when facing SS with a 1/4" bullnose HHS tool than wiht carbide, but you have to run the lathe at about 1/2 the speed.
Heat is carried away in the chips so you have to make a cut that is deep enough to make a reasonable chip, but not so deep that the lathe is working too hard. It usually better to take a shallower cut at a slight higher speed than to take a too deep cut at a low speed as that's how you can break the tool.
Another suggestion is to go to your local vocational high school and find out what text book they use in their shop course and buy one. You'll find it invaluable.
Bob